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MBarn13's avatar
MBarn13
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3 years ago

Stratix 10 SX Low Latency 40G Ethernet IP

I am attempting to use the Low Latency 40G Ethernet IP in a 1SX280HN2F43I2LPAS chip using Quartus 20.4 Pro. I am unable to get the tx_lanes_stable signal to go high or establish a link through an optical transceiver.

The locked signals from both internal PLLs miss timing to the reset synchronizers by 90+ nanoseconds. The clk_ref is being supplied a 322.265625 MHz clock that is not the correct frequency at power on and is configured through the design. The clk_status and reconfig_clk are bing supplied a 160 MHz clock.

When the clk_ref is set correctly the ATX PLL is recalibrated and then once it achieves lock the csr_rst_n, tx_rst_n, and rx_rst_n resets are asserted for 255 cycles of the 160 MHz clock.

My main questions are why are those paths failing by so much and what can I do to establish a connection?

3 Replies

  • ZiYing_Intel's avatar
    ZiYing_Intel
    Icon for Frequent Contributor rankFrequent Contributor
    3 years ago

    Hi MBarn13,

    Thanks for submitting the issue.

    Please do allow me have some time to look into the issue and I will get back to you with findings.

    Best regards,

    Zi Ying

  • ZiYing_Intel's avatar
    ZiYing_Intel
    Icon for Frequent Contributor rankFrequent Contributor
    3 years ago

    Hi MBarn13,


    The reasons that might cause tx_lanes_stable unable go high are as below:

    1. soft_tx_rst, tx_rst_n : Resets the IP core in the TX direction. Resets the TX PCS and TX MAC. This reset leads to deassertion of the tx_lanes_stable output signal.
    2. sys_rst, csr_rst_n : Resets the IP core. Resets the TX and RX MACs, PCS and transceivers. Note: csr_rst_n resets the Control and Status registers, except the statistics counters. sys_rst does not reset any Control and Status registers. This reset leads to the deassertion of the tx_lanes_stable and rx_pcs_ready output signals.


    Best regards,

    Zi Ying


  • ZiYing_Intel's avatar
    ZiYing_Intel
    Icon for Frequent Contributor rankFrequent Contributor
    3 years ago

    Hi MBarn13,


    Since I have addressed your question and no hear any feedback from you, I am now close the case. If you have any question after the case closed. Please do feel free to submit another issue.


    Best regards,

    Zi Ying